Grinding-mill.



E. F. McCOOL.

GmNmNG MILL.l

APPLICATION FILED MAY 27. |912. 1,137,224. Patented Ap?. 27, 1915.

K M 4 SHEETSAHEET l.

u, if J5/062% E. F. McCOOL.

GRINDING MILL.

APPLICATION FILED MAY27.19|2.

1,137,224., Patented Apr. 27, 1915.

4 SHEETS-SHEET 2- @wi/imm@ 314042 moz www. l@

E. F. McCOOL.

GRINDING MILL.

APPLICATION FILED MAY21. |912.

1,137,224. Patentd Apr. 27, 1915.

4 SHEETS-SHEET 3- LF. MccooL. GRINDING MILL.

APPLICATION FILED MAY 27. |912.

5 m/f. mf M. m o m 1T e 0 m Wm a r. M @M pn i e ds d e4 r/N m w r a Q`P. W

marked thereon, which form 'cumstances described, Il

Urrrrnn .srrATEs PATENT oriucn. n

EDWARD l?. MoCOOL, 0F VICTOR, COLQBADO.

` @BINDING-mmh declare the following to be a full, clear, and

exact description of the invention, such'as will enable others skilledin the art to which it appertains to make and use the same, referencebeing had to the accompanying drawings, and to the characters ofreference a part of this specification.

l My invention relates to improvements inv grinding mills, my objectbeing to provide an eiiicient construction of this class, in whichprovision is made for permitting a yielding movement in a longitudinaldirectionof the rotary member ofthe grinding head in order to preventbreakage or injury to the mechanism due to the entrance to the grindingjaws of a metal article or other foreign device which is too hard to becrushed. It sometimes happens that a metal tool, as a--wrench, isaccidentally fed, with the ore, rock or other material to be ground,into the space between the'jaws or grinding members. f j

One of the objects of my present construction is to prevent injury tothe machine due to an accident of thischaracter. While provision isLinade for ypermitting the rotary member of the hood lto move away fromits relatively stationary member under the cirso provide means frwhereby a clutch carried y the rotary hollow shaft is disconnected fromthe oper.- ating pulley from which power is transmittedto the hollowshaft through the instrumentality of the said clutch. Hence,` by

`virtue of my'improved constructionwhen the rotary grinding memberyields to prevent injury to the apparatus, .the shaft which impartsmovement to the grinding member is simultaneously Vdisconnected from thepower which drives the machine stopped. v,

Provision is further made for producing an air-current within thehousing inclosing the grinding members, whereby thepulveiized material,when reduced tothe proper whereby the moving parts" are quickly neness,isy removed from vthe housing, while particles which pass from betweenthe grindv ing Amembers into the housingand which a're Specication ofLetterav Patent.

not sufliciently ine for the purpose, will drop into a removablereceptacle and may be introduced into ythe hopper for regrinding. Theair-current is `made of-such strength and so regulated asto remove onlysuch particles as have -been properly reduced. l

Having briefly outlined my improved'construction, I will proceed todescribe the same 1n detail2 reference being made toy the accompanyingdrawing in which is illustrated an embodiment thereof.

In this drawing: Figure 1 is a longitudinal section taken through agrinding mill equipped with my improvements, parts, however, being shownin'elevation. Fig, 2 iS-a detail view of the friction-clutch' shown on alarger scale. Fig. 3 isa sectional view of the same. Fig. 4 is a .detailView of the l Patented Apr. 27, 1915. Application led May 27, 1912.Serial No. 668,907. I

the hollow shaft to an interiorly-located and y independently-movableoperating shaft, the latter being eccentrically mounted in the hollowshaft and employed `for imparting. direct rotary movement to the movablemem'- ber of the grinding head. This view is obtained by looking inthedirection of arrow 4 Fig., 1. Fig. 5 is a section taken on the line 5-5Fig. 1 looking toward the right or iii the direction of the arrowadjacent said line. Fig. 6 is a side elevation of the rear extremity ofthe machine or a view looking in the direction of arrow 6 Fig. 5. Fig. 7is a front end elevation of the machine or a view looking in thedirection of arrow '7 Fig. 1. Fig. 8 is a side elevation of the forwardextremity' of Vthe machine.,

showing the .housing and the stationary j aw swung away from the movablejaw or grind- -ing member. Fig. 9 is a side elevatinof the same showingthe'parts in the closed position. Fi 10 is asection taken on the line10-10 Fig. 1 looking toward the left.

The same reference characters indicate the same parts in all. the views.Y

Let the numeral 5 designate a suitable vframe-work in which is'journaleda hollow shaft 6 upon which is splined va frictionmember-7 adapted toengage a power-pulley 8 which' is connected with a lmotor or othersuitable ower not shown. As illustrated in thel rrawing, thisclutch-member" is composed of a hub 9'splined upon the radially-disposedmembers 13 .provided with hollow shaft by. a key 10.' .Formed integrallwwith this hub .is an open web 12 having recessesllrin whicharelocatedsleeves 15 i which vare quite loose withinthe recesses andpivotally connected with the members 13 by means of pivot-pins 16, thesaid pins 'being' located near the inner .extremities of the vsaidsleeves topermit a slight rocking movement of the sleeves with theirrespective recesses. Appliedto each member 13 forward of its sleeve 15is a rigid screw 17 located. near the outer extremity of the sleeve,which may beadjusted to regulate the swinging or tilting movement of thesleeve. On the opposite side of the sleeve and located directly acrossfrom the screw 17, is a spiral spring 18 which permits the sleeve tomove or swing rearwardly on its pivot.

Threaded into the sleeve 15 is a screw 19 which is centrally providedwith a part 20, fashioned to receive a wrench for adjusting purposes.This screw is threaded at both extremities, its outer portion -21 being4threaded into a similar sleeve 22 which is Amovably mounted on apivot-pin 23`located near its outer extremity, and threaded into thefriction member 11 of the clutch which is movable independently of thebody-member for releasing purposes. Aptplied to'this friction member inthe rear o the sleeve 22 ,is a screw 24 which may be adjusted forlimiting the movement `of the sleeve and the screw 19. l Opposite thisscrew 24 and located in a recess'also Iformed in the friction member, isa spiral spring 25, The friction member' which is connected with thesleeve 22 by the pivot-pin 23 as aforesaid, includes .-a shoe 26composed of a metal 'member 27 and a member 28 preferably compos\ed ofwood and connected with the me al memberby a suitable fastening device29. Thev inner portionof 'each friction member 11 i's recessed toreceive .the sleeve 22 which is loosely arranged therein for the samepurpose as the similar arrangement of the sleeve 15 in the recess 14 ofthe body ofthe clutch. l

By virtue of the construction and arrangei ment of the clutch,as-heretofore described,

it will be understood that by moving the same' sligli'tly rearwardlyon'the hollow shaft 6, eaclrscrew 19 willbe permitted to assume aposition slightly inclined to the normal position. In other words, by a'slight movement of the clutchmember towardl the left (see Fig. 1) on thehollow lshaft .6, the inner extremity of each ofthe screws 1,9 will ,becaused to swing slightly rearwardly, while its outer extrem1ty will lag,whereby yeach screw 19 will be slightlytiltedvsoythat its innerextremity shall be farther rearward than its outer extremity.' This willresult in moving each friction member 11 of the clutch'slightlj;inwardly whereby the clutch and consequently the 'shaft 6 isdisconnected 65 from the power pulley.

i 6 is equipped with a crank-arm 30 whose The forward extremity of thehollow shaft outer extremity is provided with a wrist-pin 31.011 which agear 32 is mounted to rotate. 4This gear travels in a relatively .largeexteriorlyllocated stationary gear 33 and meshes with a relatively smallgear 34 keyed to the operatin shaft 35 which is eccentrically mountewithin the hollow shaft 6. In this manner rotary movement is impartedtothe operating shaft at, a different speed from that of the rotaryshaft.

To the forward extremity of the operating shaft 35 is attached, as shown'at 36, a hollow bracket 37, having a forwardlylocated elongated opening38 adapted to receive a rectangular member 39 formed on a' rotary gndingmember`40, the last named member in hollow, as shown at 41,- to receivethe ace parts 42 of the hollow bracket on opposite sides'of the opening38. v

in' the rearward direction suiliciently 'to bring the part 39 within thehollow or concavity 44 of the bracketin the rear of `the face members 42of the bracket, and also in' the rear oflugs 45 which extend rearwardlyand areseparated to receive the part 39 of the grinding-head when thelatter is givenv a lquarter-revolution after inserting the part 39withinthe opening 38 of thebracket. As soon as this is done, the part 39(see Fig. 10)' may `move forwardly between the lugs 45, an as theoperating shaft 35 is normally thrust forwardly, as hereinafterexplained, while the bracket is normally thrust rearwardly; thegrinding-member 40 will be securely heldA in' operative relation withthe operating shaft. l

The bracket 37 is normally thrust rearwardly on the operating shaft by avspiral spring 46 located within the hollow of the bracket and havingits rearward extremity bearing against the rear end of the bracket onthe inside, while its forward extremity engages a stop disk 47 appliedto the forward extremity of the shaft 35. Theffor#` so lconstructed asto permit the grinding-p member a slight rocking movement on the bracketfrom a point 50 as a center. This movement will facilitate the grindingaction of the apparatus.

The interior ortion 'of the grinding-member 40, where ltvengages theexterior por- 1erv ' tively stationary grinding-member'52, which ismounted in a housing 53 hinged as shown at 54 to a stationary member 55carriedby a collar 56 surrounding the forward extremity of the hollowshaft. This housing is provided with an opening 57 through which thematerial to be ground may be'v introduced to the space between thegrinding jaws through an opening"58. f

vso

The forward extremity of the hollow shaft 6 is equipped witha collar 59which is made fast thereto and provided with fan-blades 60V which arelocated within the housing and surrounding the hollow bracket 37, beingarranged to rotate within the space of the housing into which the groundmaterial which has been reduced by the grinding members, must enter.This fan produces an air-currentI of suiicient strength to cause theproperly ground material to be discharged fromthe housing through anopening 61 .formed in an outlet 62 which may be in .communication with areceptacle of any desired character for the pulverized material.

In the rear of the housing and formed integral with the stationarycollar 56, isa hollow drum 63 provided with perforations 64,-communicating with the atmosphere. This drum also communicates with theinterior of the housing in which the fan-blades 60 are located.- Hence,as the fan is rotated; within the housing, the suction produced therebywill draw air thereinto through`the perforations 64 ofthe hollow drum.The entrance of air through these vperforations maybe regulated at willby the adjustment jof a band 65 which is rotatably mounted on the drumand provided with perforations corresponding lto those in the drum. Itwill thusbe understood that .this band mayv be adjusted by meansoi:l asuitablehandle 66 so that its perforations may fully register with theperforations 64 of the drum, or only partly register therewithy as maybedesired and according to the volume of. air which may be requiredinorder. to produce the necessary current for removing the pulverizedmaterial from the housing.

The rear extremity of the operating shaft 35 bears against a steel disk67 whichiis lol cated withinan openingv 68 formed 4in the frame-work ofthe'machine andfinterlocked as shown at 69v with a non-rotatable block70 which is longitudinallymovable within the opening .68 ofthe casing,but prevented from rotary action by means of a -key 71 secured@""to-theblock by a screw \72 and. slidable in a groove 73 formed in thecasing-,outside of `of nuts 93 which are the circumference of theopening'68.

f cated in the rear. of the block 'is `a plunger 74 inwhich -is threadeda -screw 75 equipped at its rear extremity witha handwheel 76 exposedfor manual operation.

This plunger 741is' recessed between its ex tremities as shown at 77 toreceive togglelinks 78 which also engage recesses 79 formed in blocks8() movable in hollow cylindrical members 81'1formed on the rear ex--tremity of the frame and'being exteriorly open to receiveinteriorly-projecting tongues x82 formed on cross-heads-83'and 84located respectively above and belowthe vertically movable blocks 80.These ltongues 82 are -centrally located on the cross-heads 83 and 84.4The cross-head 83 is connected at. its opposite extremities-.with rods85 by means of nuts 86 threadedxon the rods to engagementwith the top ofthe crosshead. The

lower extremities of these rods are 'connected with a cross-head 87whose opposite extremities are slidable on rods 88, there being a pairofV rods 88 at each end'of the crossfl" l, c Surrounding each rodibetween a crosshead 8 9 and .the cross-head 87, are anumber of spiral.springs 90, intermediate crossheads 91 and 92'being employed in orderto use a number of springs 90 instead of a single integral spiral springextending between each pair'of crossheads 87 and 89, thus making itpracticable to employ' relatively stili springs which are more easilymanufactured ythan a single long spring' of corresponding tension.

It will be understood that'there is a pair, of rods 88 arranged on eachside of the hollow cylindrical members 81, the two rods 88 of each pairbeing located lon opposite sides of the spiral springs. 90 and the rods'85 which are surrounded by the said springs.

The rods 88 of each pair are connected with one extremity of the cros-head 89 bv means plied to the rods above the cross-head. The oppositeeX- trernities4 of these rods areconnected with the cross-head 84 bymeans of nuts 94 located -belowthe cross-head.'v All of the crossheads87, 91 and 92 are freely'slidable onthe shown at 95 and pass through:openings formed in the opposite extremities of the cross-head 83whereby-the cross-head is freelyvslidable on this rod extension., The

object of the extensions 95 is to guidethe` cross-heads andmaintainlthem at all-A times inthe proper position,I and to prevent anytendency to get out of alinementv with the other cross-heads of theconstruction. It

will be observed that; with the exception of the rod extensions 95,-only two rods pass through the crossheads 83, namely the rods 85, onepassing through each extremity of the cross-head and in the centerthereof, the said rds being connected with the crosshead as heretoforeexplained, by nuts 86.

From the-foregoing description, it will be understood that whenever thegrinding member 40 is thrust -rearwardly from the coperatinggrinding-member 52, whereby the operating shaft is thrust endwisein'arearward direction, the blocks 80 'through the instrumentality of thetoggle-links 78,v will be thrust outwardly from the plunger 74 and thisaction, through the medium of the tongues 82, will force the twocrossheads'83 and 84 outwardly, the one moving upward and the otherdownward, whereby the. springs 90 are compressed. As soon, however, asthe obstacle interposed between the grinding members has been removed,the springs will restore the grindingfmember 40 to its normal positionwith reference to the relatively stationary grinding-head 52.

As the lower cross-head 84 is moved downwardly by virtue of theoperation hereinafter described, it acts upon a sort of bellcrank lever96 which is connected by means of arod v97 with a lever 98 toautomatically shift theclutch 7 towardthe left on the hollow shaft 6, asuflicient distance to release the clutch from the operating pulley 8,whereby the power which operates the machine is disconnected from theshaft 6 and its associated elements, thus stopping the machine. Thebell-crank lever 96 is fulcrumed as shown at 99 on a stationary part j100 of the frame-work. An arm 101 of this lever is acted on by thecross-head84, while al1/arm ..102 is connected as shown at 103 with oneextremity of the rod 97, the opposite extremity of the last-namedl rodbemg.

connected as shown at 104 with the lower extremity of lthe. member 98,the' latter being fulcrumed onf'the frame-work as shown at l f u Theupper arm ofthe lever 98 is forked, as shown at" 106, to straddle` thecollar 9 of the clutch 7, the parts of this arm on oppositevsides of thecollar being pivotally connected as Shown at 107 with a ring 108 looseon the collar 9, and engaging a circumferential groove 109 formed in"the collar. By virtue of this construction and arrangef ment, theclutch is slidably actuated on the hollow shaft 6- whenever thecross-head 84 is moved in either direction'.

Referring again to the housing 53, the latter is pivotally connected asshown at 110 with a lever-arm 111 which is pivotally connected as shownat 54fwith the bracket 55 heretofore? described.:l Intermediate theextremities of the lever-arm 111 is a recess v112 in which is ,seated/a'spiral spring 113, the said spring also Ibearing on the upper portion ofthe housing. The forward extremity of the" lever-arm 111 is providedy'posite arm 123 being equipped with with a Aface 114 which is adapted,when the housing is swung. outwardly (see Fig. 8) to be engaged by aface 115 formed on' a lug 116 of the housing.

The housing is locked in place by means of a lever-like device 117pivotally connected as .shown at118 with a stationary bracket 119 alsoconnected with the collar 56 and the drum 63.-' This device v117 extendsforwardly, from the pivot 118, and With its outer extremity is pivotallyconnected with a locking lever 120 fulcrumed on the device 117 as shownat 121. This locking lever is slightly angular in shape and is providedat one extremity with a hand-piece 122, its 0pa rounded bearingextremity 124 which is "provided with a screw-stem 125 threaded into thearm 123, whereby the part 124 is adjustable. v

The lower portion of thel housing 53 is provided with a lugl 126 whichis provided with a curved recess 127 adapted to receive the extremity124 o f the lever 120, when the housing is in the closed osition. Inother words, after the housing lias been opened to the position shown inFig. 8, in order to close it, it may be swung inwardly toward the rotarygrinding-head to the dotted-line position in Fig. 8, after which, bythemanipulation yof the lever 120, the extremity 124 may be brought intoengagement with the lug 126, and as the handle-extremity of the lever`is swung in the direction indicated bythe arrow in Fig. 8, the housingwill be thrown to its closed position, the device 117 being at the sametime raised, and the lever 120 moved to a position in alinement with thedevice 117, thus locking the housing in the closed position.

'From the foregoing description, the use and operation of my improvedgrinding millwill @e readily understood. Power is -delivered to the'machine from a suitable source (not shown) through the medium of thepulley 8, which, when the machine is in position for use, is en aged inoperative relation by the clutcl splined on the hollow shaft 6, asheretofore explained. Hence, as

the pulley is rotated, the shaft1 6 is also ro' tated, and motion issimultaneously imparted to the operating shaft 35 through themedium ofthe crank-arm 30, and the gears 32,

33 and 34: Hence, it will be understood that 'as the hollow shaft 6 isrotated, the

operating shaft l35 which is eccentrically mounted in the -hollow shaftwill have an orbital travel with the hollow shaft independently of itsrotary motion on its own axis. 40 isfnot only rotated forgrindingpurposes, but isalso given in addition a lateral or slidingmovementsimultaneously, rthus facilitating the vperformance of the grindingfunction.

Consequently, the grindingmember A:animee M.

.- Thematerial to be treated is introduced through the opening 57of-the'housing'and passes thence through the opening 58 in thestationary jaw 52, into the space between the grinding jaws 40 and 52.As this material is groundto the necessary degree of fine'- ness, itescapes from between the jaws into the interior of the housing 53 andisdriven therefrom through the medium of a current of air produced bythe fan-blades 60 `out of the housing through the opening 61, any

particles which are too large to be removed by the air-current droppinginto a slidable 'receptacle 128 which" is supported by means of acasing129, connected with the lower part of the housing.

In the event that a substance too hard to be reduced b thegrinding-members shall have been :fe thereto, the rotary grinding 20member 40 will be thrust rearwardly, to-

gether with the operating shaft 35, and by virtue of the yieldingcapacity-of the springs 90 arranged in connection with the cross-- heads83 and 84 heretofore described.

It must bdunderstood that-die grindidg I member is permitted a' slight'rocking -movement on the hollow-bracket 37 with which'it is connected..This is permitted by virtue of the curvature of the inner surface 80 ofthe member 40 where it engages a corre` spondinglycurved surface '130'ofthe said bracket. y n

,The coil spring 113 acts on. the housing 53 in the rear lof the center:of the latter .35 and at faconsiderable distance from the livot 110,whereby, as/soon as the housing is unlocked by throwing the..v lockinglever 120' t'ol the unlocked position, the spring acting omthe housing'will automatically throw 40 the latterto the open position approximatelyvas4 indicated by the dotted lines in'Fig.- 8. d

"As illustrated i' in the d-rawing, the stationary grindingmember V52 issecured to the housing by means of bolts 131. i

45. yIn order to 'notify the p'erscn'in charge of thema'chin'e that anarticle or foreign substanceof such character has passed betweengrinding members as to cause'the operat ingshaft 35`to move rearwardlyand actuate the' clutch 47 to disengage the latter `from thepower-pulley through the instrumentalityv of the connections'heretoforedescribed, an electrical" signal imay be employed. (see Fig. 1). 4Thissignal' consists, fas illustrated in the drawing, of 'a bell `132connected bymeans of' a wire1 133 f with a pole 134.- o a battery 135.The belll is also connectedby means f a wire `136 with 'a contact 137mounted Non the. frame but insulated therefrom, as

shown at 138. From the -opposite"'pole 139 of thel battery, a" wire 140lleads to a contact '141. fast. on the rod'97, 'but-insulated there-Afrom as' shdwn atf'142. The twocontacts thaving-their axes atrightangles .to the axis' .a toggle connection between the blocks and 's toact on the in an endwise by 'the movement of the lever 96; in adirection 'to act upon the lever 98 to disengage the clutch fromthepower pulley, the contact 141 will be brought into engagement withits operating contact 137, thus closing 1,0

-the battery circuit-and operating the bell It will be understood thatany suitable,

electrically operated signal may be employed, whether audible, visual orboth. v

Attention is called to the fact that in m improved construction thegrinding or pu verizing. jaws are respectively convex and its movementon its own axis, and its move- T85 ment with fthe hollow. shaft due toits ec. centric mounting therein, whereby it travels in ani orbitsimultaneously with its axial travel. Y

Having thus described my invention, what Iclaim is: 1 v

1. In an orev grinder, the combinationv oi" a grinding-member, a rotaryshaft connected 1n operative relation with said member, spring-actuatedcross-heads movable at 95 right angles to said shaft, andan operativeconnection between the said shaft and said cross-heads whereby thesprings act to imy part an endwise thrust to the-shaft in the directionolf the grinding member. v2.l In an ore grinder, the combination of agrinding-member, 'an endwise movable rotary shaft connected in operativerelation withv vsaid grinding member, coil springs 10.5 of vthe shaft,and an operative connection between said springs and the shaft to impartan endwise thrust vto the latter.

3. -Inan ore grinder, the combination of a grinding-member, an endwise-movable rotary shaft connected in operative relation with saidgrinding-member, fcoil springs having their axes at right angles-to theaxis of the Shaft, and an'operativeiconnection between said springsl andthe shaft to impart ,115 an endwise thrust to the latter, lcomprisingblocks acted on by the sprin s and movable at right angles to the axis othe shaft, and

the shaft.A

4, The 'combination of a4 grinding-member, a vrotary endwise movableshaft connected inoperative relation with the grinding- I'niember,blocks movable at right angles to the axis-Tof the shaft, cross-headsacting on vthe blocks,- springs acting on the cross-heads, 'and ato leconnection between the blocks ftheaft 'to cause the tension ofthe anglesto the axis o the shaft, atoggle connection. between the said blocks andthe shaft, cross-heads vactingl on the blocks,`

springs acting on the .cross-heads, a power pulley concentricallyarranged with reference to the shaft but loose thereon, having a clutchsplined onthe shaft and connecte in operative relation with the powerpulley and an operative connection between one of -the said' cross-headsand .the clutch, whereby, as the cross-headsare thrust outwardly by therearward movement of the shaft, the c utch is actuated to v disen agethe shaft from the power influence o? the operating pulley,substantially as described.

6. In agrinder, the combination of an endwise-movable shaft, a grindingmember connected in operative relation with one extremity of the shaft,blocks movable at right angles to the axis of the shaft, a toggleconnection between the said blocks and the shaft, cross -heads acting onthe` blocks, springs acting on the cross-heads, a power pulleyconcentrically arranged with reference to the shaft but loose thereon, aclutch splined on the shaft and connected in o erative relation with thepower-pulley, an an operative connection between one of the saidcross-heads and the clutch, whereby, as the cross-heads` are thrustoutwardly. by the -rearward movement of the shaft, the clutch isactuated to disengage the shaft from theoperating pulley, saidconnection includin a lever having'one arm in engagement wit theoperating cross-head, a second lever having one arm in engagement withthe clutch, and a rod connecting the two levers.

7. Thefjcombination of a grinding-member, a rotatable endwise-movableshaft having one extremity engaging a grinding- I so shaft to member, ahollow shaftin which the-first named shaft is eccentrically mounted, anoperating pulley loose on the hollow shaft,

a clutch splined on the hollow shaft and 4^ connected 1n operativerelationwith thesaid pulley, a. gearing connection between the hollowshaft and the first named shaft, and anf operative connection betweenthe rst 4naine shaft and the said'clutch, whereby, as the first namedshaft is thrust rearwardly, the clutch is'actuated to disconnect it fromthe power-pulley for the purpose vset forth.

8. The combination of a grinding-member, a rotary endwise-movable shafthaving one extremity in engagement with the inding-member, springs actinon the hold the lattei/ in yieldab e relation in an endwise directionwith the grindingmember, means for applying rotary motion to the shaft,and an. operative connection to the rst named shaft, a housin fan 1n salrounded end,- va socket adapted to iit said rounded end, a

vsubstantially as described.

9. In a grinder, thecombination of a ro-4 tary grinding head, a shaftconnected in operative relation with said head to rotate the same, a,hollow shaft in which the first named shaft is eccentrically mounted,means for appl ing power to the hollow shaft, and

rounding the grinding member, fan lades located in the housing andconnectedwith the hollow shaft whereby the fan blades are rotated whenthe machine is in operation, a stationary drum in communication with thehousing and having openings communieating with the atmosphere whereby,as the fan blades are rotated, a current of air is produced within thehousing of. suiiicient strength to'ex el the pulverized material throughan ou et with which the housing is provided.

10. In a grinder, the combination with an end-wise movable shaft, of agrinding member supported upon said shaft, blocks mounted for movementat right anglesto said shaft, toggle connections between said blocks andshaft, sprin tending to 4force thesaid blocks inwar y, a power pulleyconcentrically arran ed with reference to the shaft but loose t ereonhavinga clutch splined on the shaft and connected in operative relationwith the ower pulley, and an operative connection tween one of saidblocks 'and the clutch whereby as the blocks are thrust outwardly by therearward movement of the shaft the c lutch is actuated lto disenga e theshaft from the power iniiuence o the pulley, substantially as described.

11. In an ore grindelya shaft, a grinding` Imember supported upon saidshaft, means bearing upon said shaft tending normallly to thrust ityieldably forward, a powerp ley looselymounted upon said shaft andclutch acting normally to hold said shaft and pulley in operativeposition andmeans for automatically releasing said shaft under theinfluence of rearward pressure upon the same.

12. In a grinder, a casing, a grindingl member in the casing, means forimparting a planeta movement to said member, a

`casing, means for rotatin said fan about the center of revolution osaid grinding member, said casing having a passage leadingftherefromthrough which the grpd'uid material is adapted to be forced by sai an. y

ding disk having a bracket slidably mounted on said shaft and adapted`to engage said' disk and a spring 126` 13..In combination, a shafthaving a tending to hold said bracket and disk in iiXed relation.

14. In combination, a shaft having a rounded end, a grinding disk havina socket adaptedto .t said rounded en ,a iange upon the rear of saiddisk, a bracket slidably mounted upon said shaft, a iiange upon saidbracket adapted to-bear against the forward side of the flange (upon thedisk and yieldable means acting upon said bracket tending to force saidflanges together, whereby the bracket and disk are held in fixedrelation.

15. In an ore grinder, a shaft, a grinding member supported upon saidshaft, means bearing upon said shaft and tending nor- 'mally' to thrustit yieldably forward, a

power pulley loosely mounted upon said shaft and a clutch vactingnormally to hold said shaft and pulley in operative relation, and meansfor automatically releasing said shaft from the power pulley through themedium of the clutch, under the influence of rearward pressure upon thesame.

In testimony whereof I aHix my signature in presence of two witnesses.

EDWARD F. MOCOOL. Witnesses:

M. J. ONEILL, WALTER POLE.

